1 linearf (x) = mx + bone f (x) = ax 2 + bx + c, a  0quadratictwo cubicthreef (x) = ax 3 + bx 2 + cx + d, a  0 Degree Function Equation Common polynomial functions are named according to their degree. The degree of a polynomial is the greatest of the degrees of any of its terms. The degree of a term is the sum of the exponents of the variables. Examples: 3y 2 + 5x x 5 y + 3x 3 + 2y 2 degree 2 degree 6 Adding and Subtracting Polynomials

2 To add polynomials, combine like terms. Examples: Add (5x 3 + 6x 2 + 3) + (3x 3 – 12x 2 – 10). Use a horizontal format. (5x 3 + 6x 2 + 3) + (3x 3 – 12x 2 – 10) = (5x 3 + 3x 3 ) + (6x 2 – 12x 2 ) + (3 – 10) Rearrange and group like terms. = 8x 3 – 6x 2 – 7 Combine like terms. Adding and Subtracting Polynomials

3 Add (6x x –21) + (2x – 3x) + (5x 3 + x – 7x 2 + 5). Use a vertical format. 6x x – 21 2x 3 – 3x x 3 – 7x 2 + x x 3 – 7x 2 + 9x – 6 Arrange terms of each polynomial in descending order with like terms in the same column. Add the terms of each column. Adding and Subtracting Polynomials

4 The additive inverse of the polynomial x 2 + 3x + 2 is – (x 2 + 3x + 2). This is equivalent to the additive inverse of each of the terms. – (x 2 + 3x + 2) = – x 2 – 3x – 2 To subtract two polynomials, add the additive inverse of the second polynomial to the first. Adding and Subtracting Polynomials

5 Example: Add (4x 2 – 5xy + 2y 2 ) – (– x 2 + 2xy – y 2 ). (4x 2 – 5xy + 2y 2 ) – (– x 2 + 2xy – y 2 ) = (4x 2 – 5xy + 2y 2 ) + (x 2 – 2xy + y 2 ) = (4x 2 + x 2 ) + (– 5xy – 2xy) + (2y 2 + y 2 ) = 5x 2 – 7xy + 3y 2 Rewrite the subtraction as the addition of the additive inverse. Rearrange and group like terms. Combine like terms. Adding and Subtracting Polynomials

6 To multiply a polynomial by a monomial, use the distributive property and the rule for multiplying exponential expressions. Examples:. Multiply: 2x(3x 2 + 2x – 1). = 6x 3 + 4x 2 – 2x = 2x(3x 2 ) + 2x(2x) + 2x(–1) Multiplying Polynomials

7 Multiply: – 3x 2 y(5x 2 – 2xy + 7y 2 ). = – 3x 2 y(5x 2 ) – 3x 2 y(– 2xy) – 3x 2 y(7y 2 ) = – 15x 4 y + 6x 3 y 2 – 21x 2 y 3 Multiplying Polynomials

8 To multiply two polynomials, apply the distributive property. Don’t forget to apply properties of exponents!!! Example: Multiply: (x – 1)(2x 2 + 7x + 3). = (x – 1)(2x 2 ) + (x – 1)(7x) + (x – 1)(3) = 2x 3 – 2x 2 + 7x 2 – 7x + 3x – 3 = 2x 3 + 5x 2 – 4x – 3 Multiplying Polynomials

9 Example: Multiply: (x – 1)(2x 2 + 7x + 3). Two polynomials can also be multiplied using a vertical format. – 2x 2 – 7x – 3 2x 3 + 7x 2 + 3x 2x 3 + 5x 2 – 4x – 3 Multiply – 1(2x 2 + 7x + 3). Multiply x(2x 2 + 7x + 3). Add the terms in each column. 2x 2 + 7x + 3 x – 1 Example: Multiplying Polynomials

10 To multiply two binomials use a method called FOIL, which is based on the distributive property. The letters of FOIL stand for First, Outer, Inner, and Last. 1. Multiply the first terms. 3. Multiply the inner terms. 4. Multiply the last terms. 5. Add the products. 2. Multiply the outer terms. 6. Combine like terms. Multiplying Polynomials

11 Examples: Multiply: (2x + 1)(7x – 5). = 2x(7x) + 2x(–5) + (1)(7x) + (1)(– 5) = 14x 2 – 10x + 7x – 5 = 14x 2 – 3x – 5 First Outer Inner Last Multiplying Polynomials

12 Multiply: (5x – 3y)(7x + 6y). = 35x xy – 21yx – 18y 2 = 35x 2 + 9xy – 18y 2 = 5x(7x) + 5x(6y) + (– 3y)(7x) + (– 3y)(6y) First Outer Inner Last Multiplying Polynomials

13 (a + b)(a – b) = a 2 – b 2 The multiply the sum and difference of two terms, use this pattern: = a 2 – ab + ab – b 2 square of the first term square of the second term Special Cases for Multiplication

14 Examples: (3x + 2)(3x – 2) = (3x) 2 – (2) 2 = 9x 2 – 4 (x + 1)(x – 1) = (x) 2 – (1) 2 = x 2 – 1 Special Cases for Multiplication

15 (a + b) 2 = (a + b)(a + b) = a 2 + 2ab + b 2 = a 2 + ab + ab + b 2 To square a binomial, use this pattern: square of the first term twice the product of the two termssquare of the last term Special Cases for Multiplication

16 Examples: Multiply: (2x – 2) 2. = (2x) 2 + 2(2x)(– 2) + (– 2) 2 = 4x 2 – 8x + 4 Multiply: (x + 3y) 2. = (x) 2 + 2(x)(3y) + (3y) 2 = x 2 + 6xy + 9y 2 Special Cases for Multiplication

17 Example: The length of a rectangle is (x + 5) ft. The width is (x – 6) ft. Find the area of the rectangle in terms of the variable x. A = L · W = Area x – 6 x + 5 L = (x + 5) ft W = (x – 6) ft A = (x + 5)(x – 6 ) = x 2 – 6x + 5x – 30 = x 2 – x – 30 The area is (x 2 – x – 30) ft 2.